Posted
by
samzenpus
on Thursday January 15, 2009 @03:44AM
from the share-the-juice dept.

An anonymous reader writes "Researchers have developed a way to network household and commercial fridges together in a distributed peer-to-peer fashion that lets them 'negotiate' with each other on the best time to consume electricity. A retrofittable controller is attached to each fridge and then a temperature profile is built around the unit. The controller enables communication between other fridges on the network and also the power source. It enables fridges to work together to decide when to cool down, and thus consume power, based on how much surplus power will be available, and to anticipate power shortages and change their running schedules accordingly to use as little power as possible during these times."

why not simply make higher efficiency fridges? I was able to convert a chest freezer into a fridge that uses about 1/4 the energy that the best performing energy star fridge can do. It works great.

all they need to do is increase the insulation in current fridges and improve the door seals. that alone would make a HUGE improvement. Granted I get an added benefit from not having a door that empties the fridge of all it's cold air every time it's opened, but the biggest gains are from the seal and 6" of ins

What did you insulate with? I have a plan to do the same thing. Were you able to just turn down the thermostat, or did you have to bend it? And did you just add a second seal, or replace it, and if the latter, what did you replace it with?

Another measure that works well this time of year (in northern climes, anyway). Fill old bottles with tap water (plastic soda or water bottles works well). Don't fill them all the way, perhaps about 80%, then squeeze out the air and cap them.

Set them outside overnight and allow them to freeze. Place them in the fridge and viola! you've just added some really cold mass to your fridge. When the bottles have thawed, set them back outside to freeze. This is like an old-fashioned ice box, and will reduce the amount that the fridge needs to work to keep the interior cold.

I suggest using small bottles, = 1 L, so that they freeze and thaw more quickly, and so that the amount of ice in the fridge can be adjusted as food is added and removed from the fridge.

The heat loss when you open the door is a function of delta_temperature and MASS of the air exchanged. A fuller fridge will lose less of it's cold air simply because there is less cold air to lose. This is of course assuming that the fridge door is open for a relatively short amount of time, long enough for air transfer, but not long enough for the items in the fridge to sink a significant amount of the heat from the (now warmer) air.

There are real, and hard, limits on how efficient you can make them - most installed refrigerators are going to have to fit into a standard slot. Increasing insulation means losing internal capacity, and remodeling a kitchen to increase the size of the 'slot' is expensive even where practical.

Although it'd be an amusing hack I can't see the real benefit from it.

The article is looking at this as a way of using things like home renewable energy in the most efficient way.

Personally I think this is also something that would work well on the 'grid'. Power companies work most efficiently within a small band of demand, when demand falls it is inefficient for them to stop running certain plants and when demand increases the cost of activating dormant supply is high.

Fridges are fairly low power devices with naturally random and uncorrelated cycling. One would think that in any given neighborhood, the normal randomness of the many fridges' cycling would be sufficient to result in a fairly level electrical "base load". I can't see that enforcing the levelness of this distribution could actually offer very much of a reduction in the peak load on the grid. What causes excessive peak loading is the coordinated use of many high-power loads. Typically this is air conditioning in the summer - all the units run simultaneously because it's hot outside, and each unit draws about 50 times more power than a fridge. Clothes dryers and washing machines in the evening also do this to a lesser extent. In the grand scheme of things, I really don't think there's much room for improvement through load-leveling of just fridges.

It's about renewable energy and making the most of solar/wind. I.e. ensure that excess solar energy is used up during the day by cooling the fridges an extra couple of degrees so they don't have to use base load power over night.

It's about renewable energy and making the most of solar/wind. I.e. ensure that excess solar energy is used up during the day by cooling the fridges an extra couple of degrees so they don't have to use base load power over night.

I assume the idea is *not* to level the load from fridges alone, but to cut it at peak times: e.g. just before everyone switches on their kettle, flushes the loo etc during the advert break of a blockbuster movie on TV you ask *all* fridges to take break for 15 minutes to help flatten the peak.

you ask *all* fridges to take break for 15 minutes to help flatten the peak.

There's a critical difference between this system and more traditional systems that turn off things like pool pumps and water heaters. The fridge can say *no* and still turn on if it needs to in order to maintain the proper temperature for safe food(or whatever needs cooling, like vaccines). It can apparently also learn to cool things down more when there's excess power.

A single salmonella outbreak or even a need to dispose of the contents of a fridge will outweigh an awful lot of 'power savings'.

Well, there are all sorts of points of technology, even this one. But I think that a key factor of TFA is being missed by the posters here, which is that this system is meant to cool a dedicated thermal mass stored within the fridge. Unfortunately, TFA doesn't go into detail but I've seen others that do. Part of optimizing such a system is to maximize that thermal mass, maybe through such simple techniques as having people keep a few gallon jugs of water in the fridge at all times, perhaps through integrati

I was thinking the same thing when I was reading the article and comments - in order for this to be really useful you need to increase the thermal mass of the fridge so the fridge has much more play of when to turn on.

I figure a slab of concrete would be a poor choice; as you state, a couple gallons of water would give you quite a bit of thermal mass in a convienent to add/remove manner - allowing cheaper shipping, then fill the reservoir on site.

"Hey Bob, I'm cold. Do you mind turning off the tv so I can turn up the heat a bit?""Ask Steve. He's been using the oven for an hour already.""Fuck you Bob. I'm making pizzas, I won't turn my oven off.""You're a dick. Why don't you stop eating pizzas? You fat bastard.""Shut the hell up Bob. Turn off your ass dildo and you'll have power for the heat."

More's to the point, why would you need an EXTERNAL IP just for your coffee machine ?

Connect your appliances on a traditional network, then map the 10.0.0.* addresses to ports on a single external IP ?

It's one thing for you to talk to your fridge from the car, but quite another to start dealing with inter-appliance politics... "Dave, the toaster oven is being nasty to me and stealing all my power again".

For security reasons, I'd prefer to have the only outside contacts managed through some sort of central server. Wouldn't want some joker turning my fridge up to 98.6F for six hours while I'm at work. Or turning my oven onto 'self clean' for 8 hours, etc... It'd be much easier to keep 1 server secure than dozens of different devices from almost as many makers. Depending, the logic shouldn't be too hard, could even be built into future routers.

More's to the point, why would you need an EXTERNAL IP just for your coffee machine ?

Connect your appliances on a traditional network, then map the 10.0.0.* addresses to ports on a single external IP ?

It's one thing for you to talk to your fridge from the car, but quite another to start dealing with inter-appliance politics... "Dave, the toaster oven is being nasty to me and stealing all my power again".

The problem is going to be communication between the devices and the rest of the world.

We support a couple larger clients that are running some kind of IP-enabled power meters on their buildings. This lets the local power company read their meters in realtime - no estimating, no sending a guy out once a month. It gets these companies a nice discount on their electricity bill.

The way those meters are set up, the polling is initiated by the power company. We got a little worksheet from the power company th

Each device contains a controller, and the house power distribution center contains a controller. The device controllers and the house controller communicate over the power lines.

Devices must get permission from the house controller to consume the power they consume (beyond a minimal amount they are allowed to always consumer to power their controllers and sensors).

Devices tell the house how long they will need power, how long they can wait to start, whether they need the power continuously or can pause for a bit if needed, and how much they need. For example, if the fridge needs to start, but can wait a couple minutes, the house might have it wait until the microwave finishes. If the fridge says it can't wait, the house might ask the oven to stop for a a bit so the fridge can have the power to start the compressor.

Ideally, the system would be designed so that there is very little voltage and current at the outlet, until a device asks for it. Then the outlet provides the voltage and current that is asked for. Appliances plugged in but not in use would present much less of a shock hazard this way.

I'd highly recommend going with INSTEON, or building your own custom modules that use WiFi to communicate instead of the powerline. Not many houses have more than 254 outlets in them, so you'd only need a Class C of private address space for your house. I'm not sure if 254 outlets/devices can connect to a single 802.11g/n access point though.

Seriously, it's a good idea but you'll never really manage to standardise it in a way that brings in into an ordinary house ("gadget" houses and those people who already own X10 networks don't really count as "ordinary" users).

What's needed, if you're going to do this, is a universal gadget that does some *very* useful things to the average householder. I would suggest things like... water leak detectors tied into the same system that can shut off the water supply to individual devices, smoke alarms, burglar alarms, entry control, baby monitors (bring the house lights up gradually in the nursery when the baby cries) etc. all tied into the same device. The trouble is that any one facility doesn't really make a killer app and there are individual devices that do each job perfectly but the "universal" device that can demonstrate lots of useful benefits brings far too much cost into the equation (at the moment). Even X10 is prohibitively expensive for simple tasks, but I can buy a pair of remote-RF-controlled 13-amp-switching 220v mains sockets (with remote & 12V battery in every pack) for £5 from my local electronics shop.

I've often looked at automating my house... I have the hardware (opto-isolated I/O boards, relays, spare PC's, tons of logic chips and processors, not to mention cabling, wireless modules, remote sockets, sensors etc.), I have the skills (soldering, wiring, simple logic devices and processors, programming), I even have enough money to do a lot of these things. The problem is that it's much easier and cheaper to just buy a cheap baby monitor, a cheap burglar alarm, a cheap timer, a cheap energy monitor and not let them talk to each other.

However, if we were to establish a real, authenticated standard for automated house control protocols that all of these things could start supporting with a $5 chip plugged in their mains plug, then these systems would build themselves. X10 was supposed to be that, but a quick search for X10 in my country either produces lots of websites without prices at all (scary enough) or things like £50 for a single X10 mains module that then needs controllers, additional modules etc. before anything interesting can really happen (and then it is mostly basic stuff).

It's actually less than half the cost for me to buy my off-the-shelf remote-control socket, rip the remote apart (I get one with every mains module anyway, so I have a big stack of spares), take a wire from the button and plug it into a £20 USB I/O kit from Vellemans and write a bash script to do all the fancy stuff... I can already get temperature, I can already monitor electricity (again, cheaper with a £10 energy monitor from the same shop and either a bit of creative disassembly or a webcam reading the 7-segment digits off it).

This sort of stuff won't go big until there are set standards, that are ubiquitous and start getting included in *everything* (therefore cheap), so that the average homeowner ends up with at least two devices that support it without realising and then thinks "Mmm... these say they can talk together... I wonder what I need to do that?". It's how it worked with Bluetooth... nobody cared or could see the point until you are sitting in your living room with someone else who has Bluetooth and you want to exchange phone numbers etc. When enough people have it to get interest in the general populace (everyone KNOWS you can do this stuff if you have the money), then you can start standardising. But you can't standardise until enough people have it.:-)

water leak detectors tied into the same system that can shut off the water supply to individual devices

Requires a solenoid valve and power supply at each device, not to mention communication.

The REAL reason this hasn't happened yet is because no one has done it. If as you say you have all the parts and skills, why don't you put together a prototype system instead of coming to Slashdot and telling us all the reasons why you can't do it? Then you can start a company and just DO it.

99% of this stuff can be retrofit. A refrigerator in particular only needs some temp sensors run into the unit, the thermostats dia

Isn't my point that retrofit is a bit of a waste of time because it means the buyer making a specific choice to do this, whereas what's needed is ubiquity (via an established standard, e.g. BS (British Standard), ISO or equivalent specifying a protocol) so that it becomes standard, therefore attract cheap compatible devices and makes them compete on the basis of cost?

Retrofitting is a nightmare for everyone - the person doing it, the product you're doing it to, the original product manufacturer, the retrofi

There have been power control systems for quite a while to manage power consumption in factories that take things like total power draw and time of use into account. They're usually centralized instead of doing peer negotiation, though.

Florida Power & Light has offered "load balancing" boxes for decades, they switch off things like Air Conditioning under peak load conditions. My grandfather had one, they gave him $7 a month off his bill and he was happy, said it almost never did anything.

While I agree there is a potential benefit for such a system, it makes more sense to negotiate it at a whole-house level. This is superior from a privacy standpoint as well as that of complexity. Also, the system is simply more useful to the resident anyway. This is the kind of thing which could be immensely useful for people with alt.power systems.I think we would do well to focus on eliminating or making more efficient these systems which currently are so wasteful. For example, in many places you could do

Beyond even that, we have a ridiculous number of redundant appliances, how many get hot? Why should the oven, water heater, furnace, all produce a lot of heat and not share any bit of it. How many devices are heat exchangers? Air conditioning, refrigerators, water coolers, etc.

Because piping hot fluids around at low temperature differentials is expensive and inefficient. And _sharing_ waste heat isn't really a big problem. If you're heating your house, the waste heat from the water cooler, water heater, o

Living in Canada where it is -25 outside right now, I have always found it an extreme waste of energy to be powering a fridge and freezer to keep things cold in a house I am paying out the nose to heat because it is so cold outside for 1/3 of the year or more.

How come new houses aren't built with some kind of a "chill pipe", kind of like an insulated duct line that routes outside air directly into the kitchen, that could be connected to the fridge? The pipe could be automatically closed or opened as the fridge detected the temperature outside.

I have sometimes thought of a small geothermal system for a fridge/freezer. It would cycle some liquid coolant through a pipe grid buried outside, which could then be used as a heat sink for the fridge's compressor. You could even have two sets of pipes - a shallow set above the frost line for capturing the maximum cold in the winter, and a deeper set to capture the more stable 50F deeper underground.

For what it's worth, it isn't exactly the case that running the fridge inside the house during the wint

Here in Toronto it's -19 C outside (-2 F). If there were a pipe to the outside air, with a thermostat controlling flow, during Winter there would be no need to consume cooling energy at all:| This would scale to refrigerators of any size...

This probably isn't pitched at householders. I think it would be great for supermarkets, cold warehouses, booze shops, chemical plants etc... people who need commercial/industrial levels of refrigeration.

Why yes, yes it is pitched at residential AND commercial sites. This is what "Lonworks" from Echelon is all about - energy management. The technology wasn't designed for just fridges, it was designed for EVERYTHING. Lighting, heating/cooling, dishwashers, laundry, etc. With its 64 bit addressing, it is intended to allow everything to communicate, and peer communications is a big part of it (as is negotiating when to "run".)

Anyway, these researchers should talk to Echelon. They solved this problem 12 years ago.

Yeah. 'Cause I only want my lights to be on when everyone else's are off.

How about having some sort of occupancy senser, or ambient light one? Maybe some sort of automatic dimmer? On the other hand, consider commercial applications - would a billboard operator consider adding the system to the floods lighting the board if it chops his power bill in half?

The light would be pretty high up on the 'I'm using power NOW!' priority list. The important part of having lights on a system like this would be that the light is reporting it's status. This would be used to adjust the opera

Um, they have exactly that... The PP was just being flamebait. Of COURSE you wouldn't want lights being turned off on you when you are in the room.

But here is the deal.... You really don't want someone else telling you when you can run your own stuff. What you want is things like "we have a peak load time, do what you can to conserve" and YOUR controller starts taking measures to do extra conservation based on your individual needs. Likewise, "we have a surplus, rates are lower right now" so run the dishwas

Well, there's a big difference between lab simulations and real-world trials. The previous paragraph suggests the largest trial they've done with real equipment consisted of seven small fridges and three larger industrial-sized coolrooms.

Also, it's not intended for single locations but rather for "every house in the city". There's little to be gained by smoothing out the energy usage of individual locations, even rather large locations.

There's little to be gained by smoothing out the energy usage of individual locations, even rather large locations.

My first thought was this would be useful if you're forced to run on a backup generator for a while; This sort of system would allow a supermarket or a largish home to run a smaller margin by not having to worry about every compressor kicking on at once. This would allow a smaller generator, and generators run more efficiently the closer they are to their max capability.

After the fridge protocol it shouldn't be too hard to come up with other cooperative units - pumps, even a monitor on other circuits so th

There's little to be gained by smoothing out the energy usage of individual locations, even rather large locations.

I think there'd be some value to it even for a large individual location. At the very least, you could reduce the amount of electricity you use during peak hours of the day (large commercial customers are charged for electricity in part by the time of day). You could also use it to coordinate your electricity usage so that you don't have all the compressors turning on at once, which reduces

You would be surprised. A lot of people keep a second fridge (or, more often, a second freezer) in their garage or basement. There are also small "dorm" fridges that people use to keep beer, soda, whatever handy.

US fridges tend to be, well... gigantic, at least compared to the average fridge over here. That's why most people I know indeed have a second one in the garage/basement: you just cannot fit a crate of beer plus all your other fridgatives in a single fridge.

So this doesn't sound like a totally stupid idea, it might actually be a pretty good one.

Imagine you have a wind generator on your roof and several appliances connected. If the generator can't power all the devices simultaneously then they could negotiate with each other to smooth out the demand.

eg. If I put the kettle on to make a cup of tea the fridge could switch itself off for a couple of minutes. If I step in the shower all power can be diverted to the water heater, etc.

On a larger scale, smoothing out the demand could avoid building power entire power stations. This probably won't happen for the next 100 years, but one day it will.

Fridges as we know them are pretty sad contraptions with no shortage of room for improvement [typepad.com]. They put a whopping big heat source under the chamber they're trying to keep cool. They use room air from the hottest part of the house, even though in most homes that room is a foot or two away from outside air that is much cooler, if not actually even cooler than the fridge interior should be. In general, they're an agglomeration of kluges and marketroid idiocies. So yeah, this could be a key part of a rethinking of what a fridge is and how it works that could eventually cut power usage by as much as eighty to ninety percent. The same could be said of quite a lot of appliances and HVAC components. Hell, done right, we now know that comfortable homes can be built that require no conventional heating or cooling systems at all [nytimes.com].

Kinda makes you wonder why we're supposed to need this "smart grid" for all this massive increased demand we supposedly have no way to avoid, doesn't it?

Fridges as we know them are pretty sad contraptions with no shortage of room for improvement.

As long as you put energy-efficiency as your only consideration and ignore all the other things people want from a fridge. Sure, it'd be great to have a fridge that would vent its hot air to the outside in the summer (but keep it indoors in the winter), but doing that is expensive, takes up space, and (in some variants) means the fridge is no longer self-contained. Venting outside air into the fridge is also expen

Obviously, the smart fridges and other appliances will be more expensive in the first place. So the utility companies would have to offer a rebate in electricity prices for households who participate, otherwise it won't be worthwhile for individuals. Alternatively, the smart appliances could be introduced by regulation (probably a worse approach, but still possible).

The rebate approach would require smart managers, the regulation approach would require a lot of political haggling. Either way, I guess it w

So the utility companies would have to offer a rebate in electricity prices for households who participate

I don't think you'd have difficulty getting utility companies to chip in for a rebate program - they like the idea of smoothing out peak demand. In some locations you can already have the utility company install a remote switch on your home AC unit, which they can turn off during peak hours of the day. Some units have a local override, if you think you really need that AC.

Well it's not going to do anything to reduce an individual household's power usage; certainly nothing that couldn't be done with non-networked smart fridges, anyway. Most people just pay for the amount of energy they use; it doesn't matter if they consume it in large bursts or as a constant trickle.

This is intended for whole suburbs or cities to be able to regulate the energy draw from cooling fridges so as to decrease peak levels of demand. The other main thrust seems to be regarding renewable energy sources, in particular solar. The idea is that if cloud cover decreases the amount of energy being produced, the plants can tell the fridges and they can intelligently decrease their collective power draw. When the sun's out in full blaze and there's plenty of power being produced, the fridges can cool their interiors by an extra degree or two, effectively storing that additional energy to help them weather a shortage later on.

Air conditioning seems another obvious target for this technology, since most aircons cool for a while (using lots of power) and then just ran the fan (using little power) until the room heats up a bit, then they cool again. If you have 500,000 aircons all doing this, there's a good chance the power station is going to see big surges in energy draw. If they're all talking to each other, they could negotiate their cycles to place a more consistent draw on the power source, flattening out the peak.

Of course, I have no idea just how much fluctuation is common in the energy draw at our power stations, and whether this is a practical thing to pursue or just a really cool, clever idea with minimal practical applications.

Thee are locations where the price of electricity varies with day time and modern fridges (at least here in Europe) can keep cold without using electricity for hours because I suppose they are so well isolated. But you are right about the real goal of the technology i.e. decreasing but not overall consumption but the peaks - if that is done the overall capacity of network can be optimized. OC such over-optimization makes the whole thing vulnerable to any changes in consumption patterns i.e. either network c

Me too, hence my last paragraph. I don't recall ever hearing any power companies complaining about cyclical spikes in power draw as being a particular problem for them. On the other hand, they may have always just considered it a given and that there wasn't anything that could be done about it.

Humans are not random operators, especially in industrialized societies. Spikes can come in as little as fifteen to twenty seconds in a society like ours. Rush hour starts and within fifteen minutes you starts seeing a wave spreading away from centers of workplaces of air conditioners being turned on or up and lights going on as people get home. The Superbowl starts and everybody comes indoors from the barbeque to watch the game, air conditioners get turned up as

Here in Portugal (and Spain does it too) we pay a monthly fee dependent on our amperage limit, besides the normal metering. Right now we have to manually avoid having some "big" appliances like washing machines and heaters on at the same time, and when we forget it the meter limiter "halts" and we have everything unpowered 'till we wake up:(

That seems like energy conservation taken to a ridiculous extreme to me. If that's the future here then no thank you -- let's just build some nuclear plants and be done with it. What happens to customers with medical or other mission critical equipment? Is my oxygen concentrator gonna lose power because I forgot to turn the washing machine off before I go to bed?

That seems like energy conservation taken to a ridiculous extreme to me.

A model like this means that the people who use the most power pay for the production of those new energy generation facilities that you love so well, while those able to curtail their energy usage are rewarded by being charged less. It is essentially the only logical model. When we build a power plant in the USA, it costs ALL taxpayers some money, even if we live off-grid, because of bullshit subsidies and other nonsense.

Actually, I'd like that. My dryer has an automatic dry cycle, so I never know exactly how long it'll run, and the washer and dryer are in a back room that makes the alarms inaudible in the rest of the house (I have to go through the uninsulated garage to get to them, so leaving the doors open isn't an option). Now, I just watch the time and check on them when I think they should be finished, but a text message would be nice.

There will be plenty of ice cream. Only soylent green flavor, but hey...

On a downside, we will only be allowed to listen to Vanilla Ice, Ice Cube and Ice-T, and all movies will have a heroic fridge scene added to them.George Lucas once again showed us how fucking brilliant a visionary he is.

Why is this marked as troll?
Any one with a $70 embedded PC, high amperage relay, and a temperature probe could do this in a few hours.
This would only be interesting if a) all fridges used a standardized negotiation protocol b) it was extended to all high usage appliances.

Don't you think it would be a little more practical to do it with some $0.50 PIC (or $1 AVR):) chips communicating via RS-422? It could literally cost you more to buy a nice power supply than to buy the chip. And ethernet is super maximum overkill for this job. You need an intelligent/active hub/switch to tie together large numbers of RS-422 connected devices because implementation gets problematic when you have lots of things on the same current loop. But if you ran just one pair of copper (or for future

No, and most pic's cost more than $0.05 in quantities under 10,000. you also need a ethernet-> serial interface and the Xjack is the only choice for that if you want it cheap. ($18.99 in 1000 quantity.

so in production, I can add the cost of manufacture about $30.00 per fridge if you include board and programming... But I'm talking 1 off that I can buy with my credit card and get running in 20 minutes after the package arrives 2 days later.

What's your point? There are thousands of things that people "could" do that they don't. They could superinsulate their homes with dirt, straw, and a few weekend days. They could teach their kids the basics of astronomy in an afternoon or two. They could all show up at the polling place and vote for every single election. Hell, we could all build cantennas and have free wireless in every city in the world by the end of this week.

Reality isn't about what people in theory could do. It's about what they will do. And out here in the real world less than one percent of the population has the skills to do what you're suggesting and less than one percent of that one percent actually might. No comparison to a plan like this, not even taking into account the fundamental issues of determining protocols and load calculations.

And how do you "set this up at home" to negotiate with my refrigerator? You don't know who I am, or where I live. The idea they are presenting here is that your refrigerator talks to all the refrigerators in your town and they spread the times when they run their motors out over the course of the day.
Does nobody here see the privacy concerns with this idea?

Gasp! He's right! People will know when to call you and ask if your refrigerator is running! This is terrible! We must ban this before it starts to prevent those whippersnappers from tormenting us all!

Seriously. What the hell privacy issue is there with someone knowing when your refrigerator is running? Enlighten me.